Adjustment for piano-actions.



PATENTBD JULY 14, 1903. H. MALLNBRE. ADJUSTMENT PoR PTANo ACTIONS.

.m15 AN. D

' from the bottom.

Patented July 14, 1903.

.i FFICE.

PATENT HENRY MALLEBRE, OF BALTIMORE, MARYLAND.

ADJUSTMENT FOR PIANO-ACTIONS.

SPECIFICATION forming part of Letters Patent No. 733,725, dated July 14, 1903.

Application filed April l0, 1903. Serial No. 151,979. (No model.)

To @ZZ whom, t may concern.-

Be it known that I, HENRY MALLEBRE, a citizen of the United States, residing at Baltimore, State of h'laryland, have invented certain new andV useful Improvements in Adjustments for Piano-Actions, of which the following is a specification.

This invention relates to improvements in adjustments for piano-actions.

The obj ect of the invention is to provide an improved device for adjusting the key-frame and hannners with respect to the strings, whereby the quality of tone may be maintained or to increase the brilliancy of tone as might be desirable in the temporary use of the piano for concert purposes.

' "With this object in view the improved dcvice is illustrated in the accompanying drawings, in whichy Figure I is a sectional diagrammatic view of a portion of a piano employing` my invention. Fig. 2 is a vertical longitudinal section through the key-block, and Fig. 3 is a vertical cross-section through one of the keyblocks and a portion of the key-frame, Fig. 4L is a detail view of the spring-clip for holding the key-frame.

In the drawings, A designates the key-bottom and B the key-frame, which has position on said key-bottom and which is to be adjusted in a direction parallel with the strings. The keys, hammer-actions, and hammers are all mounted on the key-frame and move therewith. A key-block C has position at each end of the key-frame, although but one is shown in the drawings. These key-blocks are stationary and are secured to the keybottom, and in the present instance by dowels c and also by a screw c', which passes up through the bottom and enters the block The strings D are strung cross-wise of the key-frame and above the latter in any suitable manner, and said strings have position between the agraffe E and hammers F. 1 y

The key-bottomA is provided with suitable spring-clips a, each of which is provided with a flange a', through which latter screws CL2 are passed into the key-bottom, and these spring-clips are each provided with a rounded clamping-surface ai, which takes over the top surface of the key-frame and holds the latter down on the key-bottom, but permits the key-frame to have a sliding movement beneath said rounded surface.

The parts and mechanism so far described may have any suitable form and construction.

The key-blocks O are provided with a slot g, which has position in the side confronting the key-frame B, and this slot g extends vertically from the bottom c2 of said block. The key-block is also provided with a passage-way g', which extends in a direction at right angles to said slot g and extends across the latter and againenters the block at the opposite side of said slot. This latter portion of the passage-way g is provided with screw-threads gg, for a purpose to be hereinn after described. A pin 7L has one end secured in the side of the key-frame, and the other end of said pin projects into the slot g of the key-block and has position in the path of the passage-way g. A wood-screw i' is provided with a circiunferential groove j, and said screw extends through the passage-way g across the slot g and engages the threads g2 in the passage-way of the stationary key-block beyond the said slot g. When in position, the circumferential groove j has position in the slot g, land lthe position of the groove in said slot may be varied at will by turning the screw one way or the other. As clearly shown in Figs. 2 and 3, the circumferential groove of the screw z' fits down over the projecting end of the pin h, and as the screw 1,' is turned the pin 7L will be moved forward or backward, according to the direction the screw moves, and by such movement the key-frame B is also moved in the same direction with the pin. It will therefore be clearly understood that as the keys, hammer-actions, and hammers are all mounted on the key-frame any movement of the frame will cause a like movement to the parts mounted thereon, and therefore by turning the screw the hammers F are' moved backward or forward, as desired, beneath the strings D and agraffe E.

In order to provide for any wear that may occur to either the circumferential groove j or the pin h and to insure that ihe said pin will always be in position in said groove, I have provided a vertical adjustment for the block C, whereby the latter and the screw fi may be raised or lowered vertically to keep IOO the pin in Vengagement with thewsaid groove. This adjusting device is simple and comprises two screws k and k', the former being secured in the top :surface of the key-bottom and the latter having position in the bottom surface of the key-block and both of said screws being in alinement. In order to adjust the keyblock, andfthereby cause the pin h to take in the circuiiferential groove j, either or both of said screws 7c or /t may be turned in the proper direction to accomplish this adjustment and the key-frame is kept close to the key-bottom to prevent rattling.

It is obvious that the screw z', slot g, and passage-way g may be arranged in the keyframe and the pin h arranged in the key-block.

I-Iaving thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-

l. In apiano the combination of the strings; the key-block having a vertical slot and a passage-way extending across said slot; a screw in said passage-way and extending across said vertical slot, said screw having a circumferential groove which registers with said vertical slot; a key-frame; the hammers and hammer-action supported by said key-frame, and a pin carried by said key-frame and projecting into the vertical slot of the key-block and engaging the groove' of said screw for the purpose set forth.

2. In a piano the combination of the strings; the key-block a key-frame the hammers and hammer-action supported by said key-frame;

a screw in said key-block having' a circumferential groove; a pin carried by said key-frame for engaging the groove of said screw, and means for vertically adjusting the key-block and the screw to overcome the wear of the pin in the groove of said screw.

i 3. In a piano'the combination of a key-bottom; a key-frame movable on said key-bottom the hammers and hammer-action supported by said key-frame; the strings; the key-block; one or more screws for vertically adjusting the key-blocks with respect to the key-bottom; a screw having a circumferential groove, and a pin engaging the groove of said screw, said screw and pin coacting between the key-frame and the key-block for the purpose set forth.

4. In apianothe combination of the strings; the key-blocks; a key-frame; the hammers and hammer-action supported by said keyframe; a screw in said key-block and having circumferential groove; a pin on the forward end of said key-frame for engaging the groove cf said screw to horizontally adjust the keyframe and to keep the forward end of the keyframe on the key-bottom, and one or more spring-clips secured to the key-bottom and taking over the key-frame to hold the rear end cf the key-frame down on said key-bottom.

In testimony whereof I affix my signature in the presence of two witnesses.

HENRY MALLEISZRE. IV itnesses:

CHARLES B. MANN, Jr., G. FERDINAND VoG'r. 

